How will New Zealand get to carbon neutral? Planting trees is obvious, but may be the easy way out. Changing land use should be in the mix too, including reducing stock numbers. Rod Oram surveys the options.

Simon Upton, the Parliamentary Commissioner for the Environment, is worried we’ll take the easy way out on climate change: we’ll plant too many trees to make up for our inadequate reductions in emissions.

“I believe trading forest sinks against fossil emissions may send the wrong signal in a world that needs to significantly reduce its reliance on fossil fuels. Perhaps there should be limits on the extent to which forests should be tradeable with fossil fuel emissions. Why should the transport decisions made in Auckland strongly influence the land-use and landscapes in Otago?”

Appropriately, he delivered this and other climate change insights to an agricultural greenhouse gas forum organised recently by the NZ Institute of Agricultural and Horticultural Science. The primary sector also, most particularly dairy, is relying too heavily on forestry to offset its emissions rather than cutting them.

Upton is concerned that forestry is seen as a ‘bridge’ to buy us more time until more options are available for reducing emissions. “But it is a bridge we haven’t managed to build, let alone use. Each tonne of carbon dioxide offset through forestry is a tonne not reduced at source. If gross emissions remain high in the near to medium term, it could make it even more difficult and costly to achieve deep reductions in gross emissions in the longer-term.”

The Productivity Commission’s recent report on our pathways to a low-emissions economy, which I discussed in this column, models a very large role for forestry – as big as planting a further 2.8 million hectares of trees.

To do so, we’d need to plant for decades at a rate at which we’ve peaked only briefly in the past. Currently, forests offset just under 30 percent of our emissions. But excessive further plantings would push the share far higher.

Moreover, as Upton points out, “forestry comes with real risks.”

Land suitable for trees in economic and environmental terms is limited; those trees sequester diminishing quantities of carbon later in their life; and some are harvested before then, which depending on how the timber is used, can return some emissions to the atmosphere.

Planting the right tree species in the right place can provide significant co-benefits such as water quality and erosion control.

But those too “can have consequences for our landscapes and communities. For this reason, I suggest we need to consider other environmental objectives in the mix when developing climate policy. This means we need to think very carefully about the interactions between climate policies and policies in other domains.”

Upton will offer analysis of this in a report early next year. In the meantime, his recent speech is available here.

His message was an important one for primary sector leaders to hear at the forum. They, along with the rest of the country, can’t afford to take the easy forestry option for the next few decades in the hope of cutting emissions later. We have barely time to get this right first time. Along with everyone else in the world we have a decade at most to achieve substantial, real and permanent reductions in emissions to try to forestall catastrophic climate change.

The forum was encouraging in one sense. All 10 speakers and the organisations they represented from the dairy, sheep and beef, arable and horticulture sectors were committed to reducing emissions and have an array of programmes underway to do so.

The elephant (cow) in the room

However, four great challenges arise from their work:

– The initiatives are small scale and exploratory. None of them will be ready for deploying widely for some years. Worse, the dairy industry is hoping methane inhibitors and vaccines might reduce its cows’ emissions by a third or so in coming decades. But that’s still a science long shot which might also run into strong resistance from consumers.

– Mindsets are firmly fixed on incremental improvements in conventional farming and horticultural systems. Absent from strategies are substantial changes in land use, the foods from it, and the systems from grower to consumer to deliver them. Meanwhile, the first stirrings of such a reinvention of the global food system are underway, as I described in this column.

– The primary sector is siloed. The vast majority of dairy, sheep and beef, arable and horticulture operations (and their industry associations and researchers) are tightly focused on their specialty. Dairying is a particularly strong monoculture, which reduces its resilience in economic and environmental terms. Yet, diversification is likely to be the future of sustainable, valuable farming and the primary sector.

– Because of the silos, there was no talk at the forum about reducing ruminant animal numbers, which is inevitable for reducing the primary sector’s emissions, or of economic and other mechanisms to encourage diversification and changes in land use.

The Productivity Commission addressed these and many other impediments to reducing agricultural emissions in its final report published a month ago. Its key recommendation is to monitor emissions at the farm level and put a price on them, albeit with large, long-term allocations of free credits to reduce the actual price signal so our farmers remain cost competitive with counterparts overseas.

It believes, though, that such pricing would be the key driver of changes in land use and in the adoption of improved farming technology. In addition, it also advocates for large increases in government R&D funding to achieve the latter, and concerted policy efforts to help low emission areas of the primary sector such as horticulture and arable to develop new products and new processing, market and other infrastructure to accelerate their development.

For most of the six scenarios the Commission modelled, the reduction of land in pastoral farming would be less than the 3 million hectares the sector shed between 1990 and 2015. But a large proportion of that land went into non-farming uses, and a significant proportion was low intensity high-country land that went into the conservation estate. This time, more of the shift would be between productive sectors.

Modelling the shifts in dairy

However, the far more important past shift in pastoral land use was from sheep to dairy, with a disproportionally large increase in emissions. So, some reduction in cow numbers is essential now. Yet the Commission’s modelling varies greatly by scenarios. In two out of the six scenarios dairy land increases by 9.5 percent and production by 25 percent if methane vaccines and inhibitors eventuate. Even in the scenario least favorable to dairy, production falls only 11 percent. However, there will be large regional variations, with the bigger shifts away from dairy likely in places such as Taranaki and the Waikato.

On horticulture, the Commission modelled an increase of 100 percent to 200 percent in some scenarios, which would be substantially faster than the 44 percent (38,000 ha) increase in horticulture land between 1990 and 2015. “Also, while ample land suitable for horticulture is likely available, apparently profitable opportunities are not currently being taken up.”

Since modelling creates indicative and insightful scenarios, it is important to note a big contrast in two modelling exercises over the past 18 months. In March 2017, GLOBE-NZ, an all-party group of back bench MPs focused on the environment, received the report on NZ’s pathways to a low carbon economy it had commissioned from Vivid. 

Vivid is a UK economics consultancy with links to Lord Stern and the Grantham Institute, leaders in the field of climate change economics.

Vivid’s net zero carbon scenario, extrapolated by some later analysis by the Commission, showed our gross carbon emissions falling to 36m tonnes a year by 2050, with forestry absorbing that to make us carbon neutral.

The Commission then engaged Vivid to work with Motu and Concept, two other research bodies, to work on six scenarios on which its final report is based. Two end up at net zero, one a “disruptive” scenario has gross emissions falling to 46m tonnes a year by 2050 and the other a “stabilising” scenario with 52m tonnes. In both cases, forestry gets us to net zero.

I asked the Commission why its scenarios show less reduction in emission and a greater reliance on forestry than the original Vivid scenario. It replied that Vivid’s scenario was based on greater progress in agriculture coupled with reductions in some stock numbers, rapid take-up of electric vehicles and almost complete decarbonisation of the electricity grid.

In contrast the Commission’s disruptive scenario is based on factors such as EV’s greatly disrupting conventional vehicles, and other examples of fast technology change dislocating current industries. Its stabilising scenario sees, thanks to technology breakthroughs, an increase in dairy production but overall less reduction in agriculture emissions than Vivid’s scenario, thus requiring a much greater planting of trees.

This suggests the Commission is going too easy on dairy and too hard on forestry. To echo Upton’s analysis, we would be taking the easier way out by planting more trees rather than working harder on reducing emissions.

As a result, the biggest shift in land use would be to forestry, with a large proportion of that coming out of sheep and beef farms. While there’s certainly marginal hill country that should be treed, the lamb sector is setting itself the goal of being carbon neutral by 2050, thanks to some diversity of its land use, particularly into trees.

Therefore, it seems doubly undesirable that the modelling says we will get less lambs and more trees while dairying, which is more polluting, is less affected by changes in land use.

This would only make sense in economic, environmental and equity terms if the dairy sector makes three big commitments to: far greater, science-driven progress to drastically reduce its greenhouse gas emissions and other environmental impacts; creating and capturing far greater value from its products; and stumping up its fair share of the cost of the R&D required rather than relying heavily on taxpayer funding.

Disclosure: I was the forum’s paid MC

Leave a comment